1. Field of the Invention
This invention relates to a tire building machine and, more particularly, to a continuous and automatic second stage tire building machine and to its method of operation.
2. Description of the Background Art
Pneumatic tires of the bias type are generally built commercially in a "flat band" and subsequently expanded to the toroid shape in a curing mold. While building such tires, the strip material including the tread strips are applied directly over a laminated tire carcass while in a flat band orientation.
Conversely, pneumatic tires of the radial type are generally built commercially by the "toroid" method. This method requires a first stage tire building machine for constructing the carcass in a flat band configuration and a second stage tire building machine for constructing the breaker and tread strips and applying them to the carcass. At the second stage machine, the carcass is supported on a first drum where it is expanded into a toroid shape. The tread and breaker strips are separately built on a second drum and then transferred onto the periphery of the supported carcass to form the green tire ready for vulcanization.
Various approaches to continuous and automatic tire building machines and their components are disclosed in the literature. Note for example, U.S. Pat. Nos. 1,700,526 to Brey; 3,756,882 to Vila; 3,844,871 to Habert; 4,134,783 to Appleby; 4,197,155 to Hursell; 4,230,517 to Enders; 4,268,330 to Komatsu and 4,443,290 to Loeffler. Although many such advances are noteworthy to one extent or another, none achieves the objective of a tire building machine which is continuous and automatic, efficient, rapid and economical in its operation.
As illustrated by the great number of prior patents as well as commercial devices, efforts are continuously being made in an attempt to improve tire building machines and methods to render them more effective, rapid and economical. None of these previous efforts, however, provides the benefits attendant with the present invention. Additionally, prior tire building machines do not suggest the present inventive combination of method steps and component elements arranged and configured as disclosed and claimed herein. The present invention achieves its intended purposes, objects and advantages over the prior art devices through a new, useful and unobvious combination of component elements, with the use of a minimum number of functioning parts, at a reasonable cost to manufacture, and by employing only readily available materials.
Therefore, it is an object of this invention to provide an improved tire building machine including a first station for receiving and supporting a first stage tire carcass; a second station axially offset from the first station for assembling a breaker and tread cylinder; a servicer for feeding breaker strip material to the second station to form a breaker cylinder; a tread conveyor for feeding tread strip material to the second station over the breaker cylinder to form a breaker and tread cylinder; a transfer device to transport the breaker and tread cylinder from the second station onto the periphery of a carcass at the first station for the assembly of a green tire and to then transport a green tire to an intermediate location; a robot to transport a carcass to the first station and a green tire from the transfer ring; and control means to coordinate the movement of the servicer, conveyor, transfer ring and robot in a continuous and automatic cycle of operation.
It is a further object of the invention to provide an improved method of fabricating a green tire from a carcass on a second stage tire building system including providing a first rotatable drum for receiving and supporting a method of fabricating a green tire from a carcass on a second stage tire building system including providing a first rotatable drum for receiving and supporting a first stage tire carcass; providing a second rotatable drum axially offset from the first drum for assembling a breaker and tread cylinder; feeding breaker material to the second drum to form a breaker cylinder; feeding tread material to the second drum over the breaker cylinder to form a breaker and tread cylinder; stitching the tread material and the breaker material to the carcass; transporting, by a transfer ring, the breaker and tread cylinder from the second drum onto the periphery of the carcass at the first drum for the assembly of the green tire and then transporting the green tire to an intermediate location; transporting, by a robot, the carcass to the first station and a green tire from the transfer ring; and coordinating the movement of the breaker material, the tread material, the transfer ring and the robot by a controller in a continuous and automatic cycle of operation.
It is yet an additional object of the invention to continuously and automatically move components to and through a second stage tire building machine.
Lastly, it is an object of the present invention to build tires on a second stage tire building machine more efficiently, rapidly and economically.
The foregoing has outlined some of the more pertinent objects of the invention. These objects should be construed to be merely illustrative of some of the more prominent features and applications of the intended invention. Many other beneficial results can be attained by applying the disclosed invention in a different manner or modifying the invention within the scope of the disclosure. Accordingly, other objects and a fuller understanding of the invention may be had by referring to the summary of the invention and the detailed description of the preferred embodiment in addition to the scope of the invention defined by the claims taken in conjunction with the accompanying drawings.